In order to secure rigidity, fundamental structures of a vehicle, such as a side body and a roof, are configured with a plurality of panel members placed one on another. It is known that, when a vehicle is subjected to an unexpected impact, a load is likely to be concentrated in the area around the border between the side body and the roof among such fundamental structures. In particular, the side body needs to support the roof and is thus often set to have high rigidity, and it is confirmed through roof crash tests according to, for example, a regulation in North America (FMVSS216a) that the roof is more likely to be deformed than the side body when there are such load concentrations, which may be cause for concern.
For example, in the vehicle upper side part structure described in Japanese Patent Laid-open Publication No. 2010-221825, a reinforcing member called a gusset is attached so as to bridge the roof and a pillar of the side body. In detail, in a cross section in the vehicle width direction, the gusset is diagonally attached such that the corner between the pillar and the roof is filled. In Japanese Patent Laid-open Publication No. 2010-221825, this configuration prevents the pillar from moving toward the vehicle interior side especially in the event of side impact.
Currently, further downsizing of vehicles is required, and it is desired that the side body and other members as well as structures that reinforce them as described above have simple configurations. In this regard, the gusset of Japanese Patent Laid-open Publication No. 2010-221825 bulges toward the vehicle interior side at the corner between the pillar and the roof. Such a configuration results in a reduced cabin space, and there is room for an improvement.
In view of the aforementioned problems, an object of the present invention is to provide a vehicle reinforcing structure that has a simple configuration and that makes it possible to enhance rigidity in the area around the border between the side body and the roof.